Wireless incorporated

Gizmos are starting to be slipped inside people

THE Baja Beach Club in Barcelona is an unlikely demonstration model for wireless technology. Bikini-clad waitresses serve drinks to guests as a DJ mixes music from a motorboat perched above the dance floor. But the club made headlines three years ago when it introduced a unique form of entry ticket to its VIP area: a microchip implanted in the patron's arm.

Slightly larger than a grain of rice and enrobed in glass and silicon, the chip is used to identify people when they enter and pay for drinks. It is injected by a nurse with an intimidating syringe under a local anaesthetic. In essence, it is an RFID tag. If a special tag-reader is waved near the arm, a radio signal prompts the chip to transmit an identification number which is used to call up information about the wearer in a computer database. Otherwise the chip is dormant. The “intelligence” of the system is in the computer, not the capsule.

It is the first time that chips have been placed in humans as a means of identification and payment, gushes Conrad Chase, the club's co-owner, who came up with the idea and was the first volunteer to be “tagged”. “I know a lot of people have fears about it,” he says. But he points out that many people already have piercings and tattoos. “Having a radio-transmitting chip under your skin makes you very unique,” he says wryly.

All this for a mojito might seem a bit extreme—which for a night club is precisely the point. Even so, take-up has been low: only 94 people have been tagged in Barcelona and 70 at another Baja club in Rotterdam. But as go the bohemians, so, eventually, go the rest of us.

CityWatcher.com, an American firm that provides video surveillance in cities, has experimented with tagging two employees to give them access to areas where sensitive data are stored. VeriChip, another American company that sells chips and readers, provides it to hospitals to manage patients (though only around 200 people have so far raised their arm to get one). The idea of tagging immigrant workers in the United States has been brought up in Congress.

There is much more to come. As wireless technology improves, it is not only getting attached to machinery and embedded in the environment, but slipping under people's skin as well. And RFID capsules are small fry. There are far more advanced wireless medical devices that measure body functions and transmit the information from the skin surface or from inside the body. As the huge cohort of baby-boomers grows older and becomes more interested in preventive medicine, people now aged 50 or younger are quite likely to have some form of wireless gizmo attached or implanted in their lifetime.

Wireless technology has been used in medicine for decades. Pacemakers rely on a basic wireless system to set a stable heartbeat. Ultrasound and X-ray technologies are wireless. But as microchips become more powerful, devices shrink and battery life is extended, a host of companies are vying to take wireless technology deep into the human body.

Some wireless devices are ingested. Others are implanted. Some are attached to the body and linked to a network. It is still early days, but the systems are improving fast. “The basic technology to make these things happen exists; the big issue is how to make this economically viable,” says Maarten Barmentlo, the chief technology officer of Philips's consumer health-care division.

Inside story

Already a gaggle of gadgets is available for specialised uses. Take the PillCam, developed by Given Imaging in Israel, a tiny two-sided camera the size of a very large pill which patients swallow. It has been used in more than half a million gastro-intestinal endoscopy tests since 2001. One version is used to diagnose disorders of the oesophagus and another for those of the small intestine. It snaps a pre-set number of pictures per second and sends them wirelessly to a data recorder worn on the patient's waist. The images are downloaded to a computer for diagnosis. The $450 capsule passes through the bowel naturally and is flushed down the toilet.

This method lets people go about their normal business for most of the eight-hour test, during which up to 50,000 images are generated. It marks a vast improvement on an older technique that involves pushing a long tube through a patient's digestive tract. Although that procedure allows doctors to take tissue samples, it is uncomfortable and risks irritating the tract. Now Given Imaging is in clinical trials with a wireless camera for inspecting the colon, and is developing another for the stomach. The company faces competition from Olympus, a Japanese camera-maker, which is using similar technology.

Other wireless systems are implanted in the body. Medtronic, a large medical-device-maker, is developing many products that use wireless communications. Last year it won regulatory approval for an implantable defibrillator that links up with hospital equipment or a home monitoring device. Along with three other companies—CardioMEMS, St Jude Medical and Remon Medical Technologies—Medtronic is racing to market a device for congestive heart failure, which afflicts many millions of people worldwide. Once implanted, the device will measure pressure and fluid inside a patient's heart and wirelessly send the data to an external unit. With regular monitoring, patients will be alerted to abnormalities at an early stage.

There are two ways of making the wireless work, marking a division in the industry about the future of wireless technology in health care. Medtronic and St Jude currently make large-matchbox-sized devices—in essence, miniaturised computers—that are implanted in the chest and connected to the heart with leads, but can be interrogated wirelessly from outside the body by a reader at close quarters.

A more novel approach involves either radio waves or ultrasound technology. CardioMEMS uses radio-frequency technology, activating the chip in the implanted device by a reader that sends a burst of energy (like an RFID tag) to which the device responds with the heart-pressure information. Remon relies on a form of ultrasound that transmits energy to power the chip and prompt it to send back its pressure readings. Because the electromagnetic frequencies it uses are low, the reader can be farther away.

All four companies' heart-failure devices are still at the trial stage. In March Medtronic suffered a setback when a panel at America's Food and Drug Administration rejected its device, called Chronicle, because the trial data showed it to be insufficiently effective. Meanwhile, Remon is applying its technology to what it calls “intra-body wireless communications”. By dividing up the signal, this allows several devices inside the body to relay information to each other or to a receiver without interference, just as a radio can be tuned to different stations. So an implanted glucose-level reader in one part of the body could communicate with an implanted insulin-pump elsewhere, says Hezi Himelfarb, the boss of Remon.

Such scenarios are not so far from being realised. Sensors for Medicine and Science (SMSI) is developing a glucose sensor to be placed just under the skin of the forearm that connects to a watch-like wireless reader. This will probably become the most common way of deploying the technology: not by surgery deep into the body, but by inserting a sensor below the skin that can last for months or years, and having a wireless reader nearby.

This is the method used by Thomas Ferrell of the University of Tennessee, who has developed an implantable capsule that measures ethanol concentration in the blood. He says it could be used by alcoholics who volunteer for monitoring as an alternative to prison. The technology, funded by the National Institute on Alcohol Abuse and Alcoholism, is currently being tested in animals. Dr Ferrell expects it to become available commercially within two years.

Listen to me

Earlier Dr Ferrell spearheaded a DARPA initiative to create a tiny chip that would fit into a person's ear and monitor vital signs such as body temperature, pulse and blood pressure. The work was put on ice five years ago because of the huge cost of developing the technology that was available at the time. But now that the cost has fallen and the technology improved, the project is becoming feasible. Later this year the work is due to be resurrected by a start-up, Senior Vitals, to produce sensors for monitoring elderly people.

The technology to monitor people's vital signs already exists: NASA does it for astronauts in flight. But for the moment there is no business model for applying it on the ground, no IT system to manage it and no company that could carry out the work. As with M2M communications, any system would have to be tailor-made, which would make it very expensive. And as with other wireless devices, powering the electronics is a problem.

Belle Mellor

But companies are beginning to show interest in the sector. Adi Gan of Evergreen Venture Partners, a venture-capital fund in Israel, says that numerous business plans in this area have crossed his desk in recent months. He sees a lot of promise. For example, a doctor might implant a sensor during surgery to offer far better post-operative monitoring and care. When the patient comes for a follow-up visit, the doctor's reader would power the chip, which would provide medical information. Tiny devices could even be used for treating diseases. They might be powered wirelessly to, say, burn new cancer cells in an area that had previously been treated.

Such uses of wireless seem far removed from the mobile phones which vast numbers of people carry with them at all times. But there is a connection. As the use of wireless medical devices grows, the best way of collecting the data and sending them to a remote monitoring centre may turn out to be the patient's mobile phone, which will be close enough to receive data from the low-powered implanted device. It could be the critical bit of infrastructure between wireless communications in the body and the global internet. Just when people are starting to think of the mobile phone as a wallet, they find that it is becoming the family doctor too.

Mobile-phone operators understand the potential. South Korean and Japanese carriers are experimenting with technologies that let people monitor their heart rate, blood pressure and other vital signs with home devices and transmit the data using a phone. Philips and GE are adding wireless technology to patients' home-monitoring devices. Yet today's mobile networks are not sufficiently reliable for anything other than non-critical uses, according to a study in 2005 from the University of Massachusetts in Amherst. And the operators' current pricing models are a major barrier, says Matt Welsh of Harvard University, who is developing sensors for the continuous monitoring of vital signs.

For now the advances are largely coming from the IT industry, not the medical sector, which is noted for its conservatism. Whereas pharmaceutical firms are starting to use RFID tags on medicine packages as an anti-counterfeiting measure, other companies are working to put RFID tags onto individual pills. In January Kodak filed for a patent on an edible RFID tag which could be used, for example, to examine the digestive tract or check whether a patent has taken his medication.

It all seems a long way from the Baja Beach Club, where Mr Chase goes about his nightly routine. He reviews images from security cameras, some of which are wireless, and then locks an office with keys using a wireless ID system that records who enters where and when. The geeky stuff is his doing, but then he has form. Back in the 1980s, long before opening his nightclub, he served in the US Army Signal Corps, working on the ARPANET, the military precursor to the internet.